A series of studies will be conducted to examine the nature of codes utilized in reading. The studies deal with how orthographic, phonological, lexical, and semantic codes are used in foveal and parafoveal vision during reading. In the experiments, readers'eye movements will be monitored and the primary technique involves making display changes in the text contingent upon the position of the readers'eyes. Eye movement data (fixation time, saccade length, fixation probability, and number of fixations) will be examined to determine more precisely (1) how different codes are used in accessing the meaning of fixated words, (2) how attention is deployed during reading, and (3) how the various codes (visual, orthographic, lexical, phonological, and semantic) are used in integrating information across fixations. Many of the experiments deal with college aged skilled readers, but we will also investigate these issues in elderly and beginning readers, as well as readers of Chinese. In addition to the empirical work, we will further develop the E-Z Reader model to account for a broader range of data, and also extend it to account for eye movement behavior in beginning and elderly readers, as well as Chinese readers. The experiments and the modeling work should make it possible to better understand skilled reading and why some people do not read well.